60 GHz millimeter wave communications is an emerging short-distance high-speed radio communications technology that is defined on a 60 GHz band. Because countries over the world have up to several GHz unlicensed spectrums near the 60 GHz band, the 60 GHz millimeter wave technology has enormous communication capacity. With a WPAN (wireless personal area network) defined by using the 60 GHz millimeter wave technology, it can be convenient to implement high-speed interconnection between mobile devices and wireless display of mobile devices on a large-sized television set, display or projector. In addition, ultra high-speed download and synchronization can be implemented in hotspot areas, and Gbps (billions of bits per second, indicating a capability level of network switching bandwidth) Internet access is available, which enhances users' Internet experience. Therefore, it is attracting wide attention over the world. By now, two 60 GHz standards, ECMA 387 (European Computer Manufacturers Association) and IEEE 802.15.3c (Institute of Electrical and Electronics Engineers, American Institute of Electrical and Electronics Engineers), have been released, and another standard IEEE 802.11ad is under formulation.
All existing 60 GHz millimeter wave standards have defined a method for sending a WPAN physical layer signal, and a typical frame structure of the method is shown in FIG. 1. In the frame structure, an STF (short training field) is a short training sequence part, and CE (channel estimation) is an auxiliary sequence used for channel estimation. The STF is formed of sixteen Ga128 sequences and one —Ga128 sequence, and the CE is also formed of ±Ga128 and ±Gb128, as shown in FIG. 2. Both Ga128 and Gb128 are Golay sequences that are 128 in length. During sending of a physical layer signal based on this frame structure, a receive end may use the STF to perform burst frame capturing, frequency offset estimation and compensation, phase offset estimation and compensation, timing error estimation and compensation, and the like; use the CE to perform channel estimation; and then restore information of a frame header (Header) and a data block (BLK).
Impact of a non-ideal radio frequency factor is not taken into full consideration in the technical solution of the existing method for sending a physical layer signal. For a 60 GHz millimeter wave signal, due to a high frequency and large bandwidth, there is inevitably impact of a non-ideal factor on a radio frequency component. Typically, there are nonlinear impact and impact of IQ (inphase, inphase component; quadrature, quadrature component) imbalance, which are generated in a power amplification process, on the radio frequency component. Although some blind estimation-based solutions are available for the nonlinear impact and the IQ imbalance that are generated in a power amplification process, for a 60 GHz system, a receiver is too complex and lacks feasibility. In addition, in the Ga128-based frame capturing, multipath energy cannot be used to improve robustness of capturing, and, due to too large carrier frequency offset of the 60 GHz system, the capturing can only be performed by using a differential coherence method. A related detector produces relatively good detection performance in an ideal channel. However, under impact of channel multipath, the performance of the detector significantly deteriorates. In addition, although a multiple correlation method can resist carrier phase offset, rotation phases are different under impact of large frequency offset, and a correlation value is relatively greatly affected, which affects performance of capturing.